Update tests and documentation for supported languages.

[lyx.git] / development / PAINTING_ANALYSIS

diff --git a/development/PAINTING_ANALYSIS b/development/PAINTING_ANALYSIS
index f734edb3b012aea63443808e1aa3fdbf4ecfdab7..a52a036aaa882ffa316da458fbd5ff44be8aa9a7 100644 (file)
--- a/development/PAINTING_ANALYSIS
+++ b/development/PAINTING_ANALYSIS
@@ -20,15 +20,9 @@ following section. Some actions are proposed.
 
 ** SinglePar update
 
 
 ** SinglePar update
 

-The flag Update::SinglePar is set in many places but never acted on.
-Instead, metrics update is skipped whenever the recorded height of
-current paragraph did not change and Update::Force was not specified.
-Is it better to keep that (which incurs extra work) or to condition it
-on Update::SinglePar? If the first solution is kept, the flag
-SingleParUpdate shall be removed.
-
-Moreover, I fail to see (yet) where the 'single' part of the program
-is acted on.
+This flag only has an effect in the current BufferView, but I think it
+is useful in other views too. Doing this will require some work on the
+update pipeline, though.

 
 ** Buffer::change issues
 
 
 ** Buffer::change issues
 


@@ -40,6 +34,7 @@ a good value? NoScreenUpdate?
 On a related note, what is the semantics of a call to
 Buffer::changed(false)? What does the caller mean?
 
 On a related note, what is the semantics of a call to
 Buffer::changed(false)? What does the caller mean?
 

+

 ** How to avoid redraw with FitCursor when the cursor is already OK?
 
 In this case, we invoke Buffer::change(false) with drawing disabled
 ** How to avoid redraw with FitCursor when the cursor is already OK?
 
 In this case, we invoke Buffer::change(false) with drawing disabled


@@ -60,11 +55,35 @@ cursor.
 
 * Clean-up of drawing code
 
 
 * Clean-up of drawing code
 

-The goal is to make painting with drawing disable fast enough that it
-can be used after every metrics computation. Then we can separate real
-drawing from metrics.
+** Set Row::changed() in a finer way
+
+*** singleParUpdate
+
+When the height of the current paragraph changes, there is no need for
+a full screen update. Only the rows after the current one need to have
+their position recomputed.
+
+This is also true when scrolling (how to do that?)
+
+*** redoParagraph
+
+It should be possible to check whether the new row is the same as the
+old one and keep its changed() status in this case. This would reduce
+a lot the amount of stuff to redraw.

 
 

-Other changes are only clean-ups.
+** Put labels and friends in the Row as elements
+
+It should not be necessary to access the Paragraph object to draw.
+Adding the static elements to Row is a lot of work, but worth it IMO.
+
+** Create a unique row by paragraph and break it afterwards
+
+This should be a performance gain (only if paragraph breaking still
+shows as expensive after the rest is done)
+
+** do not add the vertical margin of main text to first/last row
+
+Would make code cleaner. Probably no so difficult.

 
 ** When a paragraph ends with a newline, compute correctly the height of the extra row.
 ** Merging bv::updateMetrics and tm::metrics
 
 ** When a paragraph ends with a newline, compute correctly the height of the extra row.
 ** Merging bv::updateMetrics and tm::metrics


@@ -76,7 +95,7 @@ insets. We should re-use the bv::updateMetrics logic:
  + transfer all the logic of bv::updateMetrics to tm.
  + Main InsetText should not be special.
 
  + transfer all the logic of bv::updateMetrics to tm.
  + Main InsetText should not be special.
 

-The difficuly for a tall table cell for example, is that it may be
+The difficulty for a tall table cell for example, is that it may be

 necessary to break the whole contents to know the width of the cell.
 
 
 necessary to break the whole contents to know the width of the cell.
 
 


@@ -109,15 +128,22 @@ DecorationUpdate). It triggers a recomputation of the metrics when either:
  + Update::Force has been specified
  + Update::FitCursor has been specified and there is a need to scroll
    the display.
  + Update::Force has been specified
  + Update::FitCursor has been specified and there is a need to scroll
    the display.

- + the current paragraph, after rebreak, does not have the same height as in
-   existing metrics. Note that the Update::SinglePar flag is *never*
-   taken into account.
+ + Update::SinglePar has been specified and the current paragraph has
+   not changed height.
+
+If a computation of metrics has taken place, Force is removed from the
+flags and ForceDraw is added instead.
+
+It is OK to call processUpateFlags several times before an update. In
+this case, the effects are cumulative. processUpdateFlags executes the
+metrics-related actions, but defers the actual drawing to the next
+paint event.

 
 The screen is drawn (with appropriate update strategy), except when
 update flag is Update::None.
 
 
 
 The screen is drawn (with appropriate update strategy), except when
 update flag is Update::None.
 
 

-** Metrics computation
+** Metrics computation (and nodraw drawing phase)

 
 This is triggered by bv::updateMetrics, which calls tm::redoParagraph for
 all visible paragraphs. Some Paragraphs above or below the screen (needed
 
 This is triggered by bv::updateMetrics, which calls tm::redoParagraph for
 all visible paragraphs. Some Paragraphs above or below the screen (needed


@@ -127,6 +153,9 @@ tm::redoParagraph will call Inset::metrics for each inset. In the case
 of text insets, this will invoke recursively tm::metrics, which redoes
 all the paragraphs of the inset.
 
 of text insets, this will invoke recursively tm::metrics, which redoes
 all the paragraphs of the inset.
 

+At the end of the function, bv::updatePosCache is called. It triggers
+a repaint of the document with a NullPainter (a painter that does
+nothing). This has the effect of caching all insets positions.

 
 ** Drawing the work area.
 
 
 ** Drawing the work area.